Soil Survey of Lincoln County, West Virginia - Soil Data Mart - US ...

Soil Survey of Lincoln County, West Virginia
Classification of the Soils
The system of soil classification used by the National Cooperative Soil Survey has
six categories (Soil Survey Staff 1999, 2003). Beginning with the broadest, these
categories are the order, suborder, great group, subgroup, family, and series.
Classification is based on soil properties observed in the field or inferred from those
observations or from laboratory measurements. Table 22 shows the classification of
the soils in the survey area. The categories are defined in the following paragraphs.
ORDER. Twelve soil orders are recognized. The differences among orders reflect
the dominant soil-forming processes and the degree of soil formation. Each order is
identified by a word ending in sol. An example is Alfisol.
SUBORDER. Each order is divided into suborders primarily on the basis of
properties that influence soil genesis and are important to plant growth or properties
that reflect the most important variables within the orders. The last syllable in the
name of a suborder indicates the order. An example is Udalf (Ud, meaning humid,
plus alf, from Alfisol).
GREAT GROUP. Each suborder is divided into great groups on the basis of close
similarities in kind, arrangement, and degree of development of pedogenic horizons;
soil moisture and temperature regimes; type of saturation; and base status. Each
great group is identified by the name of a suborder and by a prefix that indicates a
property of the soil. An example is Hapludalfs (Hapl, meaning minimal horizonation,
plus udalf, the suborder of the Alfisols that has a udic moisture regime).
SUBGROUP. Each great group has a typic subgroup. Other subgroups are
intergrades or extragrades. The typic subgroup is the central concept of the great
group; it is not necessarily the most extensive. Intergrades are transitions to other
orders, suborders, or great groups. Extragrades have some properties that are not
representative of the great group but do not indicate transitions to any other
taxonomic class. Each subgroup is identified by one or more adjectives preceding the
name of the great group. The adjective Typic identifies the subgroup that typifies the
great group. An example is Typic Hapludalfs.
FAMILY. Families are established within a subgroup on the basis of physical and
chemical properties and other characteristics that affect management. Generally, the
properties are those of horizons below plow depth where there is much biological
activity. Among the properties and characteristics considered are particle-size class,
mineralogy class, cation-exchange activity class, soil temperature regime, soil depth,
and reaction class. A family name consists of the name of a subgroup preceded by
terms that indicate soil properties. An example is fine, mixed, superactive, mesic Typic
Hapludalfs.
SERIES. The series consists of soils within a family that have horizons similar in
color, texture, structure, reaction, consistence, mineral and chemical composition,
and arrangement in the profile.
Soil Series and Their Morphology
In this section, each soil series recognized in the survey area is described.
Characteristics of the soil and the material in which it formed are identified for each
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